Knitting machine



July 18, 1944.

A.. SHORTLAND 2,353,973

KNITTING MACHINE Filed March.22, 1943 3 Sheets-Sheet l I nvenlor,flrt'har' Shortland;

A torn July 18, 1944. A SHORTLAND 2,353,973

KNITTING MACHINE I Filed March 22, 1945 s Sheets-Sheet 2 F/GZ.

In venior firth ur Short land,

By W

Allard;

July 18, 1944.

A. SHORTLAND' 73- KNITTING MACHINE Filed Mar ch 22, 1943 3Sheets-Sheet-3 V In ventor flrthur Short la nd,

By I Atlor y Patented July 18, 1944 UNl'lED STATES 'nm'r'rme MACHINEArthur Shortland, Leicester, England, assignor to Mellor Bromley and Co.Limited, Leicester,

England Application March 22, 1943, Serial No. 480,074

In Great Britain December 31, 1941 1c- Claims. (Cl. 66-126) Thisinvention comprises improvements in draw mechanism for rotary andstraight bar knitting machines of the type having a line of needles andat least one element which, in the knitting process, is reciprocatedlengthwise of said line and the amplitude of travel of which requires tobe varied. In the most important application of this invention the saidelement is a thread carrier or carrier bar. In machines of this type (ofwhich the Cottons Patent is the modern example) the draw mechanism bywhich the thread carriers are reciprocated commonly comprises a frictionrod which is reciprccated with a constant amplitude (usually by a rotarydraw cam which drives a piv oted draw lever through the medium of a drawbar having trucks engaging the periphery of said cam) and carries atleast one friction box that is connected to any selected carrier bar;the amplitude of traverse of the latter is variably determined byadjustable end stops so that when the traverse of a carrier bar isterminated by contact with an end stop the friction rod slides throughthe box for the remainder of the traverse of said rod. Hence shock andfrictional losses are inseparable from this known mechanism, and theobject of the present invention is the provision of variable drawmechanism which obviates friction boxes and is not subject to these adisabilities.

The present invention provides, in a knitting machine of the typespecified, draw mechanism comprising a cam track, a follower, engagingsaid track, for movement to and fro thereby,

which follower is connected to the reciprocating 85 element, and meansfor modifying said track to vary the amplitude of travel of saidelement. According to a feature of the invention there are two membersthat are simultaneously oscillatable, a cam track formed on the twomembers 40 and comprising a helical part on one and a part of reducedpitch with a lead-in thereto on the other, and means for eflectlngrelative circumferential and axial adjustment between said two membersto vary the length of the cam track 46 while keeping the lead-inblending with the helical part of the track. More specifically the saidmechanism may comprise a cam having a helical cam track, mounted foroscillation (or rotation to and fro) about its longitudinal axis, and soan annular member, at least at one end of said cam and partaking of thesaid oscillation, having a circumferential track for the follower and alead-in track portion blending into the helical helical track to thecircumferential portion and vice versa. It will therefore be appreciatedthat by this adjustment of the annular member the effective axial lengthof the cam track is varied with a corresponding variation in thetraverse of the carrier bar or other element. In general there will bean annular member aforesaid at each end of the cam; in some cases thetwo members will be adjusted symmetrically and in others differingadjustments will be imparted to hem.

The foregoing and other features of the invention set out in theappended claims are incorporated in the constructions that will now bedescribed with reference to the accompanying drawings, in which Figure 1is an elevation, to some extent diagrammatic, showing a draw camaccording to the invention and associated parts;

Figures 2 and 3 are sectional views showing certain details;

Figure 4 is a cross section through a Cottons Patent orother straightbar or rotary knitting machine incorporating the invention;

Figure 5 is a perspective view showing carrierlocating mechanism.

The draw mechanism comprises a cylindrical drum l0 mounted on a shaft Hwhich is oscillated first in one direction and then in the other 9 bysuitable mechanism. This drum H) has its periphery cut with a helicalcam track or groove E2 the axial length of which is such as to providethe maximum length of draw required. This groove I2 is engaged by afollower I3 which is connected by mechanism hereinafter described to athread carrier bar it or any selected carrier bar so that as the cam isoscillated to-andfro the carrier bar is reciprocated. Surrounding eachend of the drum there is a sleeve (15a, l5b) which is sliclable androtatable on it, each sleeve having a peg E6 or its equlvalentengagedinthe helical. track I2. Each sleeve also has a circumferential track Itcut into it for somewhat less than 360; one end l8 of thiscircumferential track is blind and the other end l8" merges with acurved lead-in portion into the helical-track I2. It will therefore beappreciated that as the sleeves I511, I512 are adjusted axially on thedrum l0 they rotate thereon in such manner that the said lead-inportions 18 always register with the helical track l2 and the efiectivelength of the cam trackis thus varied. As the drum in revolves thefollower i3 traverses the helical track 12 and towards each end of therotation in either track whereby the follower may pass from the 5sdirection passes from the track in th drum by circumferential portion ofthe track IS on the appropriate sleeve. The curved blending portionprovides for the deceleration of the follower, and the circumferentialportion provides for a rest period thereof. Likewise when the drumreverses the follower travels in the reverse direction and the curvedblending portion ll" accelerates the follower from rest.

It will be appreciated that the track I! in each sleeve is of necessityformed at a greater radius than that of the track in the drum, and thatpro vision must be made for the follower to pass smoothly from one tothe other. For this purpose each sleeve Ilia and Nb is provided at theend of its curved blending portion ll" with a ram'p l9 which engages inthe helical track It, and the follower I3 is spring loaded (by meansindicated diagrammatically at 20) to ride up and down the ramp I! inpassing from the helical track I! to the blending portion l8" and viceversa.

The sleeves lia, b are adjusted in any suitable manner. For example theymay each be provided with an annular collar or groove ll engaged by ashoe or slipper II which is moved axially of the drum through suitablemechanism. These shoes or slippers may be moved by the fashioning screwsthrough connections indicated at 22, or by a separate screw -23 whichmay be operated in step with the fashioning screws. It is desirable,however, that the step-by-step variations in the draw should beaccurately and positively determined. For this purpose the interior ofeach sleeve Ha, lib is provided with a series of annular grooves 24 thepitch of which corr sponds to the minimum step in the draw variations;for example'the grooves may have a twoneedle pitch. Extending lengthwiseof the drum Ill in its interior there is a roller 25 mounted to rwkabout an eccentric axis 28 which extends parallel with the drum axis.This roller 25 (or at least each end of it) is grooved in a similarmanner, and it is so arranged that owing to its eccentricity it may berocked between a locking position in which it engages the grooves 24 inthe sleeves and an inoperative position in which it is buried within theperiphery of the drum. Means are provided for rocking it to the lockingposition after the sleeves lia, lib have received each adjustment, andto the inoperative position preparatory to each adjustment of thesleeves. For this purpose the roller may be provided with a forked arm21 projecting from the drum periphery and adapted to engage a strikingpin 28 as the drum oscillates.

This striking pin may itself be movable into and out of operativeposition.

The application of the present draw mechanism to a Cottons patent orother rotary or straight.

bar knitting machine is illustrated in Pig. 4. This figure only showsthose parts of the machine that .are desirable to identify it (such forexample as the cross frame I! incorporating front rail 8|, k rail 3template'rail 38 and head rail 84,

and the needles II and sinkers It) or are helpful in understanding theinvention, since the remainder or the machine is well understood in theart and needs no illustration or description herein.

'I'hecamdrum" It occupies a rearwardly inclined attitude at the back ofthe machine, and

the mechanism for oscillating it about its axis is in this exampleillustrated as consisting of a draw cam -31 rotatingat an appropriatespeed (I eiproeated lengthwise of the on the camshaft 88 and oscillatinga draw lever 38 to the free end of which a rack 40 is connected; thelatter drives a shaft II that extends horizontally lengthwise of themachine and is connected to the drum i0 through bevel gearing 42. Thefollower I3 is carried by a bracket 43 travelling on guides 44 and hastwo carrier racks 45, 46 connected to it. The rack is for the maincarrier rods Na and rack 48 is for the plating carrier rods lib and inorder to preserve. the requisite plating lead the plating rack 48 isdriven through a lost-motion connection comprising a finger 41 onbracket 43 working between spaced stops 48 on the rack. The racks 45, llrespectively drive pinions 49, 50 that are movable axially intoengagement with the required carrier rods by mechanisms 5|, 52, saidrods being provided with racks of teeth as shown in Fig. 5.

Means are also preferably provided for ensuring that the carrier bars IIare located correctly and positively at each end of their particulardraw, and after each narrowing movement. In this, use is made of theracks of teeth with which they are provided which teeth may have atwo-needle pitch. Associated with said racks there is a plateor othermember 53, Fig. 5, carrying teeth which are adapted to mesh with thoseof the racks. At the end of each draw, this plate is brought intoengagement with the teeth of all the carrier bar racks, and preparatoryto and during each draw it is disengaged from the racks to permit theselected carrier bar to be traversed. One mechanism for controlling thiscarrier-locking device is indicated at 54 in Fig. 4.

The sleeves 15a, |5b may be adjusted in con,- formity with theadjustment of the fashioning screws 55 of the fashioning mechanism 56(itself of well understood construction) so that as the fabric underproduction is narrowed or widened the draw is correspondingly adjusted.One

. means for effecting this is diagrammatically illustrated in Fig. 4.One rack mechanism 51 for the screws 55 is operated by a truck lever 58having other for driving the left-hand splicing carrier.

9. third for driving the split foot and block toe carriers. Thesemechanisms may be arranged substantially as in Fig. 4. In the case ofthe splicing carriers the two sleeves of each drum are given differingadjustments because one end of the traverse of each splicing carriermust correspond to a selvedge edge of the blank and the other end of itstraverse must correspond to the inner margin of the splicing. Thereforethe sleeve at one end of each splicing drum may be controlled by thesame mechanism that controls the sleeves of the main carrier drum (e. g.by

means such as that illustrated in Fig. 4 control- I ling the fashioningscrews), and the sleeve at drum by a sepa draw cam partaking ofmovements about an axis and the amplitude of travel or draw of whichelement requires to be varied, which draw mechanism comprises anoscillatory draw cam provided with a cam track, a follower, engagingsaid track, for movement to and fro thereby which follower is connectedto the reciprocating element, and means for modifying said track to varythe amplitude of travel of said element.

2. Mechanism according to claim 1, comprising two members that aresimultaneously scillatable, a cam track formed on the two members andcomprising a helical part on one and a part of reduced pitch with alead-in thereto on the other, and means for effecting relativecircumferential and axial adjustment between said two members to varythe length of the cam track while keeping the lead-in blending with thehelical part of the track.

3. Mechanism according to claim 1, comprising a cam having a helical camtrack mounted for oscillation about its longitudinal axis, and anannular member at least at one end of said cam and partaking of saidoscillation, having a circumferential track for the follower and aleadin track portion blending into the helical track whereby thefollower may pass from the helical track to the circumferential portionand vice versa.

4. Mechanism according to claim 1, comprising a cam, having a helicalcam track, mounted for oscillating about its longitudinal axis, anannulan member at each end of said track and partaking ofsaid'oscillation, each of which members has a circumferential track forthe follower and a lead-in track portion thereto, blending into thehelical track, for thev passage of the follower from the helical trackinto the circumferential portion and vice versa, and means for adjustingsaid members axially to vary the amplitude of travel of said element.

5. Mechanism according to claim 1, comprising two members that aresimultaneously oscillatable, a cam track formed on the two members andcomprising a helical part on one and a part of reduced pitch with alead-in thereto on the other, a ramp between the helical track and thelead-in, and means for effecting relative circumferential and axialadjustment between the two members to vary the length of the track whilekeeping the lead-in blending with the helical part of the track;combined with means for permitting the follower to give in travelling upand down the ramp.

6. Draw mechanism for a straight bar knitting machine of the type havinga line of needles and at least one element which in the knitting processis reciprocated lengthwise of the line of needles and the amplitude oftravel or draw of which requires to be varied, which draw mechanismcomprises a cam itself comprising two members that are simultaneouslyoscillatable, and a cam track formed on them and comprising a helicalpart on one and a part of reduced pitch with a lead-in thereto on theother; a locating device on the member formed with thelead-in forengaging in said helical part of the track andfor causing the lead-in toblend with said helical part during relative axial and circumferentialadiustment between the two members, means for 7. Draw mechanism for astraight bar knitting machine of the type having a line of needles andat least one element which in the knitting process is reciprocatedlengthwise of the line of needles and the amplitude of travel or draw ofwhich requires to be varied, which draw mechanism comprises a draw cam,means for oscillating it, and a follower connected to the reciprocatingelement and movable to and fro by the cam, and which draw cam comprisestwo members that are simultaneously oscillatable, a cam track formed .onthe two members and comprising a effecting said adjustment, a followerengaging.

helical part on one and a part of reduced pitch with a lead-in theretoon the other, means for effecting relative circumferential and axialadjustment between said members to vary the effective length of the camtrack and the draw of the aforesaid element whil keeping the leadinblending with the helical part of the track, and means for locking thetwo members in the position to which they are adjusted.

8. For a straight bar knitting machine of the type having a line ofneedles and at least one carrier which, in the knitting process, isreciprocated lengthwise of the needles to feed thread thereto and theamplitude of travel or draw of which carrier requires to be varied; drawmechanism for said carrier which comprises a single oscillatory draw camhaving a cam track, a follower engaging said track for movement to andfro thereby, means connecting the follower to the. carrier, and meansfor modifying said track to vary the draw of the carrier.

9. In a straight bar knitting machine of the type having a line ofneedles, a carrier which, in the knitting process, is reciprocatedlengthwise of the line of needles to feed thread thereto, and fashioningmechanism including points that are displacea'ble along the line of theneedles; the combination with means for moving said points lengthwise ofthe line of needles, of draw mechanism for the carrier which mechanismcomprises an oscillatory draw cam having a cam track,,a followerengaging said track for movement to and fro thereby, a connectionbetween said follower and carrier, and means for modifying said track tovary-the amplitude of travel or draw of the carrier in accordance withthe said movement of the fashioning points.

10. In a knitting machine of the type having a line of needles, a threadcarrier movable along said line of needles to feed thread thereto, andfashioning mechanism, including screws and means for racking them, forfashioning the edges of the fabric being produced,

in which machine the draw of the carrier requires to be varied inconformity with the operaof which members has a circumferential trackand a lead-in track portion blending into the aforesaid helical track,means for oscillating said cam and annular members, a follower forengaging said track and for passing between the helical part and thecircumferential parts by way of the lead-in portions during saidoscillation, and means for racking said annular members towards and awayfrom one another as the fashioning screws are racked.

, ARTHUR SHORTLAND.

fashioning

